xref: /third_party/skia/gm/bitmapshader.cpp (revision cb93a386) 
1/*
2 * Copyright 2013 Google Inc.
3 *
4 * Use of this source code is governed by a BSD-style license that can be
5 * found in the LICENSE file.
6 */
7
8#include "gm/gm.h"
9#include "include/core/SkBitmap.h"
10#include "include/core/SkCanvas.h"
11#include "include/core/SkColor.h"
12#include "include/core/SkImageInfo.h"
13#include "include/core/SkMatrix.h"
14#include "include/core/SkPaint.h"
15#include "include/core/SkRect.h"
16#include "include/core/SkShader.h"
17#include "include/core/SkSize.h"
18#include "include/core/SkString.h"
19#include "include/core/SkTileMode.h"
20#include "include/core/SkTypes.h"
21#include "include/gpu/GrRecordingContext.h"
22#include "src/gpu/GrCaps.h"
23#include "src/gpu/GrRecordingContextPriv.h"
24
25namespace skiagm {
26
27static sk_sp<SkImage> draw_bm() {
28    SkPaint bluePaint;
29    bluePaint.setColor(SK_ColorBLUE);
30
31    SkBitmap bm;
32    bm.allocN32Pixels(20, 20);
33    bm.eraseColor(SK_ColorRED);
34    SkCanvas(bm).drawCircle(10, 10, 5, bluePaint);
35    return bm.asImage();
36}
37
38static sk_sp<SkImage> draw_mask() {
39    SkPaint circlePaint;
40    circlePaint.setColor(SK_ColorBLACK);
41
42    SkBitmap bm;
43    bm.allocPixels(SkImageInfo::MakeA8(20, 20));
44    bm.eraseColor(SK_ColorTRANSPARENT);
45    SkCanvas(bm).drawCircle(10, 10, 10, circlePaint);
46    return bm.asImage();
47}
48
49class BitmapShaderGM : public GM {
50
51protected:
52    void onOnceBeforeDraw() override {
53        this->setBGColor(SK_ColorGRAY);
54        fImage = draw_bm();
55        fMask = draw_mask();
56    }
57
58    SkString onShortName() override {
59        return SkString("bitmapshaders");
60    }
61
62    SkISize onISize() override {
63        return SkISize::Make(150, 100);
64    }
65
66    void onDraw(SkCanvas* canvas) override {
67        SkPaint paint;
68
69        for (int i = 0; i < 2; i++) {
70            SkMatrix s;
71            s.reset();
72            if (1 == i) {
73                s.setScale(1.5f, 1.5f);
74                s.postTranslate(2, 2);
75            }
76
77            canvas->save();
78            paint.setShader(fImage->makeShader(SkSamplingOptions(), s));
79
80            // draw the shader with a bitmap mask
81            canvas->drawImage(fMask, 0, 0,  SkSamplingOptions(), &paint);
82            // no blue circle expected (the bitmap shader's coordinates are aligned to CTM still)
83            canvas->drawImage(fMask, 30, 0, SkSamplingOptions(), &paint);
84
85            canvas->translate(0, 25);
86
87            canvas->drawCircle(10, 10, 10, paint);
88            canvas->drawCircle(40, 10, 10, paint); // no blue circle expected
89
90            canvas->translate(0, 25);
91
92            // clear the shader, colorized by a solid color with a bitmap mask
93            paint.setShader(nullptr);
94            paint.setColor(SK_ColorGREEN);
95            canvas->drawImage(fMask, 0, 0,  SkSamplingOptions(), &paint);
96            canvas->drawImage(fMask, 30, 0, SkSamplingOptions(), &paint);
97
98            canvas->translate(0, 25);
99
100            paint.setShader(fMask->makeShader(SkTileMode::kRepeat, SkTileMode::kRepeat,
101                                              SkSamplingOptions(), s));
102            paint.setColor(SK_ColorRED);
103
104            // draw the mask using the shader and a color
105            canvas->drawRect(SkRect::MakeXYWH(0, 0, 20, 20), paint);
106            canvas->drawRect(SkRect::MakeXYWH(30, 0, 20, 20), paint);
107            canvas->restore();
108            canvas->translate(60, 0);
109        }
110    }
111
112private:
113    sk_sp<SkImage> fImage, fMask;
114
115    using INHERITED = GM;
116};
117
118DEF_SIMPLE_GM(hugebitmapshader, canvas, 100, 100) {
119    SkPaint paint;
120    SkBitmap bitmap;
121
122    // The huge height will exceed GL_MAX_TEXTURE_SIZE. We test that the GL backend will at least
123    // draw something with a default paint instead of drawing nothing.
124    //
125    // (See https://skia-review.googlesource.com/c/skia/+/73200)
126    int bitmapW = 1;
127    int bitmapH = 60000;
128    if (auto ctx = canvas->recordingContext()) {
129        bitmapH = ctx->priv().caps()->maxTextureSize() + 1;
130    }
131    bitmap.setInfo(SkImageInfo::MakeA8(bitmapW, bitmapH), bitmapW);
132    uint8_t* pixels = new uint8_t[bitmapH];
133    for(int i = 0; i < bitmapH; ++i) {
134        pixels[i] = i & 0xff;
135    }
136    bitmap.setPixels(pixels);
137
138    paint.setShader(bitmap.makeShader(SkTileMode::kMirror, SkTileMode::kMirror,
139                                      SkSamplingOptions()));
140    paint.setColor(SK_ColorRED);
141    paint.setAntiAlias(true);
142    canvas->drawCircle(50, 50, 50, paint);
143    delete [] pixels;
144}
145
146//////////////////////////////////////////////////////////////////////////////
147
148DEF_GM( return new BitmapShaderGM; )
149
150}  // namespace skiagm
151